Severe obstructive sleep apnea in a child with melanocortin-4 receptor deficiency.

Obstructive sleep apnea (OSA) is a highly prevalent medical condition in obese children and is associated with significant neurocognitive, cardiovascular and metabolic derangements. Monogenic forms of obesity resulting from disruption of the leptin-melanocortin pathways have become more notable in recent years and distinguish between various obese phenotypes. However, the association of such disorders with OSA is not well established in children or adults. In this report, we describe a 23-month-old female with morbid obesity and OSA, who was found to carry a defect in the melanocortin-4 receptor (MC4R) pathway. This report emphasizes the genetic basis of obesity related to MC4R deficiency and OSA in children.